Detachable wheel.



J'. V. PUGH.

DETACHABLE WHEEL.

APPLICATION man mm. 5. m2.

Patented Mar. 4, 1919.

3 5HEETS-SHEETI Fig.6.

l. V. PUGH.

DEIACHABLE WHEEL.

MPLLCAUUN man MAR. 5, 19:2.

1296316 Patented Mar. 1919 P l v In 1 iISHEETS-SHEEH.

i g V 4 r mmgsses UNITED sTArEs PATENT OFFICE.

JOHN VERNON PUGH, OF COVENTRY, ENGLAND, ASSIGNOR, BY MESNE ASSIGNMENTS, '10 WIRE WHEEL CORPORATION OF AMERICA, A CORPORATION OF NEW YORK.

DETACHABLE WHEEL.

Specification of Letters Patent.

Patented Mar. 4, 1919.

, hub part being held thereon by means of a nut part-or equivalent screwed member.

The object of the invention is to render the securing of the nut or screwed member which holds the outer upon the inner hub part independent of the action of the ratchets or other additional locking device, which have hitherto been regarded as essential in practice to insure safety.

It is Well known that if two solids of revolution, cylinders, cones, screw-threaded cylinders or the like are put together one inside the other the inner one must be smaller than the outer one and consequently must be of shorter circumference and under conditions that keep the two parts in contact at one fixed point and substantially out of contact at the diametrically op osite fixed point, if either of the two parts e revolved then the other part will revolve also and the speeds of revolution of the two parts will be proportional inversel 1 to the relative lengths of their circum erences the inner part revolving faster than the outer part.

The invention consists in applying this principle so as to obtain automatic retention of detachable outer hub parts on inner hub parts indiscriminately on either side ofa vehicle.

The invention also consists in the improvements in detachable wheels as hereinafter indicated.

Referring now to the accompanying drawingsz- Figure 1 is a diagram illustrating the principle upon which the invention is based.

Fig. 2 is a plan of a motor car to which this invention isoapplied, fitted with four detachable wheels and carrying a spare wheel part interchangeable with any one of the four.

Fig. 3 shows the outside ends of a pair of wheel hubs for use on opposite sides of a vehicle to which this invention is applied.

Fig. 4 shows another way of carry ng the invention into effect.

Fig. 5 shows a modified form of screw thread. i

Fig. 6 is an enlarged fragmental, section of the ends of the wheel hubs upon each side of a vehicle, and

Fig. 7 is a similar drawing to Fig. 6 but showing a modified form of the invention.

In Fig. 1 the circles AB represent the cross section of two solids of revolution fitting the one within the other, the necessary clearance being exaggerated for the sake of clearness. If these two bodies are pressed together in a vertical direction as indicated by the arrows CD and the one A is .re-

volved in the direction of the arrow E, then the other B will be driven by it and will revolve as indicated by the arrow F, but at a higher speed of revolution in the ratio" of the diameter A to the diameter B.

When applying the foregoing to a detachable wheel hub construction, the nut part which is provided with circumferential engaging surfaces forming solids of revolution has each pressed by the weight of the car tightly in contact with one of two other solids of revolution in the shape of the engaging surfaces of the inner and outer parts, the two former having of necessity the same angular velocity when revolving. The nut part will during joint revolution of the parts tend to move forward or backward rela-' tive to either one of the two hub parts according to whether it is in contactwith an internally disposed or an externally disposed circumferential engaging surface difference. According to a third alternative, the frictional drivin efi'ect of one of the hub parts ma be practically eliminated by arrangin riction reducing means between its circum erential engaging surface and the corresponding engaging surface of the nut part.

The present application describes only cases of the first ty e in which the movement of the nut is t e result of the sum of the two driving efi'ects acting in the same direction. The other cases are described in applications Serial Nos. 710481 and 719207. In carrying this invention into efi'ect in one form, as shown by way of example in Fig. 3, an outer hub part, a, is mounted upon an inner hub part, 6, some usual known form of enga ing means such as serrations or the like, icing provided so that the two parts rotate together. A moderately coned centering abutment is provided at the inside end of the inner hub and the outside end of the inner hub part is made to project beyond the end of the outer hub part, and is provided with an externally facing screw thread, r. The external surface, m, of the end of the outer hub part is made of a slightly tapered conical form the smaller diameter being at the outside end. The nut, 0, screws upon the thread, 1-, provided on the inner hub part, and has a circular V-shaped roove, g, on its inner side, one surface. 0 the groove bears u on theconed surface, m, of the end of t outer hub part while the surfaces, 1', and, Z, are so arranged that they cannot come into contact. The'ordinary' clearance between the inner and outer hub parts which is found necessary to insure an easy attachment and removal of the detachable parts of thewheels is such that when the lock nut is screwed up, a'vertical force due to gravity -will be transmitted through. the lock nut from one hub part to the other. The contact between the inner hub part and the nut will have thetendency to make the latter rotate at a slower speed than the former, owing to the property already described and there will also be, due to the contact between the nut and the outer part, a tendency-for the former to revolve at a slower speed thanthe latter. The inner and outer hub partsbeing rotationally locked together the before mentioned engaging means andthe tendency to relative movement of the nut with re ardto both of thegn being the same, it 'wi be clear that by suitably arranging the hand of the thread employed, the nut may be caused constantly to screw up or on to theinner hub part, and there w1ll be no tendency forit unscrew or become loose. V D

If a ri ht handed thread is employed upon the left and sideof the vehicle, and a left hub part, a, is made to project beyond the end of the inner hub part, b, and its outside end, 7', is sli htly coned or bell-mouthed. The inner hu' part, b, is provided with an internal screw thread, It, and the nut, a, is-

formed with an enlarged conical part, l, which fits within the bell-mouthed portion, 7', and engages the surfaces l of the outer hub part, the inside end of the nut, screwing into the internal thread, is, of the inner hub part.

By this arrangement it is again possible to cause the tendencies to relative movement of the nut to be the same at regards direction with regard to both the inner-and outer hub parts, due to the nature of its contact therewith, the nut tending to revolve faster than both hub parts and to remain in its screwed up position as before described, in this case a left hand thread is provided on the left hand side of the vehicle and a right hand thread on the right hand side.

In a further modification shown in Fig. 5, the inner hub part, b, is provided with an external thread, m, of undercut or dove-tail form, upon which the nut screws. There is a clearance provided between the horizontal portions of the screw thread, so that the nut comes into contact with the thread only upon the inclined or undercut surfaces, which form of contact is of the same nature as an internal thread. The outside end "of the outer hub part is bell-mouthed, as in the previous modification, and the nut is provided with an enlarged end which fits within this bell-mouth. In this Way it will be again clear that the contact with the inner and outer hub parts both produce the same eifect upon the nut, and by the use of suitably handed threads which will be the same in the last arrangement, this effect may be made to keep the nuts screwed up in poslcase a right-hand thread is employed upon the right-hand side of the vehicle, and a lefthanded thread upon the left-hand side, the

lock nuts on both sides will always tend to tighten up and to remain in'posltion with regard to their respective inner hubs.

I have found by experiment that the tightening up of,the lock nut will continue until the outer hub part is more nearly or perfectly concentric with the inner hub part and the pressure between the contacting surfaces is so great that the additional force of gravity is not suflicient to produce any difl'erence in the disposition of the lock nut relative to the hub parts, and that when this has taken place reversal of the vehicle does not loosen the wheels.

In the form of the invention already described, it will be seen that the lock nuts, as well as the inner hub parts for opposite sides of a vehicle are dissimilar to one another having a right-hand thread on one side of the vehicle and a left-hand thread on the other, a nut cannot therefore be attached to and carried about by the outer hub of the wheel which is applicable to either side of the vehicle but in a modified form of the invention as shown in Fig. 4, the lock nut is retained in connection with the outer hub part a by the withdrawal ring 0! which is kept from loosenin by the grub screw e.

The lock nut w ien tightened up abuts against an external coned surface in formed at the end of the outer hub part and it is provided with a portion of a right-hand thread f and a portion of a left-hand thread g, which portions are of difierent diameters and can engage external threads of the correct hand provided on the inner hub parts on opposite sides of the vehicle so that in this instance only the inner hub parts are dissimilar to one another for opposite sides of a vehicle and the outer hub parts and nuts are alike on both sides. The lock nut in this modification is external to the surfaces of revolutions with which it contacts on both the inner and outer hub parts, and it will in accordance with the principle already described, revolve at a slightly slower speed than the hub parts during joint revolution. If the inner hub parts are provided with a right-hand thread on the left-hand side of the vehicle and a left-hand thread on the right-hand side, the lock nuts will always be tightened up and retained in position. The right-hand thread f is made of such a diameter that it will ass over the left-hand thread on the inner ub part without engaging therewith.

As stated in describing the form of the invention shown in Fig. 4 a lock nut which engages with internal surfaces of the hub parts requires a right-hand thread upon the right-hand side of the vehicle, while in de-' scribing Fig. 3 it is shown that the one that contacts with external surfaces engages with abutment surfaces suitable for engagement by both types of lock'nut and so be applicable to either side of the vehicle.

It will be seen that by the use of th is 1nvention a spare wheel part which is interchangeable with any of the like detachable wheel parts of a vehicle is automatically and safely retained in position as soon as the lock nuts have been screwed up, and that no spring or hand operated pawls or catches with the attendant ratchet teeth or castellations are necessary to prevent the lock nut from working loose, and as the lock nut automatically tightened up there is no posslbility of the outer hub part remainin loose upon the inner hub part through insu cient tightening of the lock nut, and undue wear of the driving members is thus avoided. Further, any ordinary spanner of the cor- .rect sizemay be used for the lock nut and no special pawl releasing devices are required, the spanner may also be instantly applied to the lock nut for tightening or unscrewing without the previous manipulation of any catches or pawls; it is therefore fool-proof.

It will also be clear that many modifications may be made in this invention and in the manner of carrying it into eflect without in any way departing from the spirit of the same.

Having now described my invention what I claim as new and desire to secure by Letters Patent is 1. In a detachable wheel the combination of an inner hub part, an outer hub part mounted on said inner hub part to revolve therewith but subject to a slight eccentric displacement, and a nut pressed tightly in contact with both said eccentrically displaced hub parts and given a rotative move ment by the driving eflcct from both said parts, said nut engaging a similarly disposed surface of each hub part so that the relative movement transmitted to said nut is the sum of the driving eficcts of both p n-ts acting in the same direction.

2. In a detachable wheel the combination of an inner hub part, an outerhub part mounted on said inner hub part to revolve therewith but subject to a slight eccentric displacement, and a nut having one surface contact ing one side of said inner hub part and a second surface contacting a similarly dispbsed side of said outer hub part whereby said nut has a tendency to rotate relatively to both said hub parts, one of said surfaces and its contacting hub part having a suitably arranged threaded engagement so that the relative rotation of the nut and hub parts tends to tighten up the nut during the forward movement of the wheel.

3. In a detachable wheel the combination of an inner hub part, an outer hub part mounted on said inner hub part to revolve therewith but subject to a slight eccentric and the other of said surfaces and its contacting hub part having a suitably arranged threaded engagement so that the relative rotation of the nut and hub parts tends to tighten up the nut during the forward move ment of the wheel.

4. In a detachable Wheel the combination of an inner hub part, an outer hub part mounted on said inner hub part to revolve therewith but subject to slight eccentric displacement, and a nut having one surface contacting one side of said inner hub part and a second surface contacting a similarly disposed side of said outer hub part whereby said nut has a tendency to rotate relatively to both said hub parts, the nut and inner hub part contacting surfaces having suitably arranged threaded engagement so that the relative rotation of the nut and hub parts tends to tighten up the nut during the forward movement of the wheel.

5. In a detachable wheel the combination of an inner hub part, an outer hub part mounted on said inner hub part to revolve therewith but subject to slight eccentric displacement and a nut having one surface contacting one side of inner hub part and a second surface contactin a similarly disposed side of said outer iub part whereby said nut has a tendency to rotate relatively to both said hub parts, the nut and outer hub part contacting surfaces being tapered and the nut and inner hub part contacting surfaces having a suitably arranged threaded engagement so that the relative rotation of the nut and hub parts tends to tighten up the nut during the forward movement of the wheel.

6. In a detachable Wheel the combination of an inner hub part, an outer hub part mounted on said inner hub part to revolve therewith but subject to slight eccentric displacement, said inner hub part having its outer end threaded and said outer hub part having its outer end tapered and a nut having a threaded surface to engage the threaded end of said inner hub part and a tapered surface to engage the tapered end of outer hub part, both threaded and tapered surfaces of said nut being similarly disposed, whereby said nut has a tendency to rotate relatively to both hub arts, said tendency being the sum of the driving effects between the nut and inner hub part and the nut and outer hub art in the same direction.-

7. In a etachable wheel the combination of an inner hub part,an outer hub part mounted on said inner hub part to revolve therewith but subject to slight eccentric displacement, said inner hub part having its outer end externally threaded, said outer hub part having its outer end externally tapered, and a nut having an internal threadedsurface to engage the externally threaded end of said inner hubpart, and

mounted on said inner huh part means in;

suring simultaneous rotation of said parts but permitting eccentricity of their axes,and' a nut having an internally screw threaded surface engaging the screw threaded end of said inner hub and an internal surface engaging1 the outer side of the endof said outer ub'part. r

9. In a detachable ,wheel the combination of an inner hub part, an outer hub part mounted on said inner hub part, a coned abutment at the inside end of said inner hub part on which said outer hub part rests, means insuring simultaneous rotation of said parts but permitting eccentricity of their axes, the outer end of said inner hub part having an externally facin screw thread, and .a nut having an interna ly screw threaded part engaging the outer 'end of said inner hub part and provided with a circular groove on the inner side into which the outer end of said outer hub art projects with the nut contacting with t e outer side of said hub part.

10. In combination an inner hub art of a detachable wheel for the right si e of a vehicle, an outer part sleeved on said inner part, means insuring simultaneous revolution of said parts but permitting eccentricity of their axes, a circumferential engaging surface to each of said parts, at least one of said surfaces being screw-threaded, a nut part, circumferential engaging surfaces to said nut, complementary to said hub surfaces whereby it transmits radial forces while retaining one part upon the other and due to eccentricity rotates relative to said parts during revolution of the wheel, and three i parts of a wheel for the left side of a vehicle equivalent to the aforesaid and with the outer and nut parts interchangeable with said right hand outer and nut parts but with engaging surfaces so differentiated that the relative rotation upon forward movewant of a vehicle tightens the nut upon earh side.

11. In combination an inner hub part for the right hand side and one for the left hand side of a which, screw threads in connection with said parts. and dissimilar f r the two sides. an outer huh part indiscriminately fitting upon either inner part. and screw threads in connection with said outer part complelm-ntary to the two dissimilar threads of said inner parts.

12. In combination an inner hub part for the right hand side and one for the left hand side of a vehicle, srl'ow threads on both said parts and dissimilar for the two sides, an

outer hub part indiscriminately fitting upon either inner hub part, and a nut provided with two sets of screw threads complementary to the two dissimilar threads of said inner hub parts for securing said outer hub part to an inner hub part on either side of the vehicle.

In testimony whereof, I afiix my signature in presence of two witnesses.

JOY'LN VERNON PUGH. Witnesses B. H. MA'rrHEws, THOMAS H. WEST. 

